Fix an uninitialised variable (key) in afs_alloc_anon_key() by setting it
to cell->anonymous_key.  Without this change, the error check may return a
false failure with a bad error number.

Most of the time this is unlikely to happen because the first encounter
with afs_alloc_anon_key() will usually be from (auto)mount, for which all
subsequent operations must wait - apart from other (auto)mounts.  Once the
call->anonymous_key is allocated, all further calls to afs_request_key()
will skip the call to afs_alloc_anon_key() for that cell.

Fixes: d27c71257825 ("afs: Fix delayed allocation of a cell's anonymous key")
Reported-by: Paulo Alcantra <pc@manguebit.org>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Paulo Alcantara <pc@manguebit.org>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: syzbot+41c68824eefb67cdf00c@syzkaller.appspotmail.com
cc: linux-afs@lists.infradead.org
cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull vfs fixes from Christian Brauner:

 - afs: Fix delayed allocation of a cell's anonymous key

   The allocation of a cell's anonymous key is done in a background
   thread along with other cell setup such as doing a DNS upcall. The
   normal key lookup tries to use the key description on the anonymous
   authentication key as the reference for request_key() - but it may
   not yet be set, causing an oops

 - ovl: fail ovl_lock_rename_workdir() if either target is unhashed

   As well as checking that the parent hasn't changed after getting the
   lock, the code needs to check that the dentry hasn't been unhashed.
   Otherwise overlayfs might try to rename something that has been
   removed

 - namespace: fix a reference leak in grab_requested_mnt_ns

   lookup_mnt_ns() already takes a reference on mnt_ns, and so
   grab_requested_mnt_ns() doesn't need to take an extra reference

* tag 'vfs-6.18-rc8.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
  afs: Fix delayed allocation of a cell's anonymous key
  ovl: fail ovl_lock_rename_workdir() if either target is unhashed
  fs/namespace: fix reference leak in grab_requested_mnt_ns

The allocation of a cell's anonymous key is done in a background thread
along with other cell setup such as doing a DNS upcall.  In the reported
bug, this is triggered by afs_parse_source() parsing the device name given
to mount() and calling afs_lookup_cell() with the name of the cell.

The normal key lookup then tries to use the key description on the
anonymous authentication key as the reference for request_key() - but it
may not yet be set and so an oops can happen.

This has been made more likely to happen by the fix for dynamic lookup
failure.

Fix this by firstly allocating a reference name and attaching it to the
afs_cell record when the record is created.  It can share the memory
allocation with the cell name (unfortunately it can't just overlap the cell
name by prepending it with "afs@" as the cell name already has a '.'
prepended for other purposes).  This reference name is then passed to
request_key().

Secondly, the anon key is now allocated on demand at the point a key is
requested in afs_request_key() if it is not already allocated.  A mutex is
used to prevent multiple allocation for a cell.

Thirdly, make afs_request_key_rcu() return NULL if the anonymous key isn't
yet allocated (if we need it) and then the caller can return -ECHILD to
drop out of RCU-mode and afs_request_key() can be called.

Note that the anonymous key is kind of necessary to make the key lookup
cache work as that doesn't currently cache a negative lookup, but it's
probably worth some investigation to see if NULL can be used instead.

Fixes: 330e2c514823 ("afs: Fix dynamic lookup to fail on cell lookup failure")
Reported-by: syzbot+41c68824eefb67cdf00c@syzkaller.appspotmail.com
Signed-off-by: David Howells <dhowells@redhat.com>
Link: https://patch.msgid.link/800328.1764325145@warthog.procyon.org.uk
cc: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org
cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>

As well as checking that the parent hasn't changed after getting the
lock we need to check that the dentry hasn't been unhashed.
Otherwise we might try to rename something that has been removed.

Reported-by: syzbot+bfc9a0ccf0de47d04e8c@syzkaller.appspotmail.com
Fixes: d2c995581c7c ("ovl: Call ovl_create_temp() without lock held.")
Signed-off-by: NeilBrown <neil@brown.name>
Link: https://patch.msgid.link/176429295510.634289.1552337113663461690@noble.neil.brown.name
Tested-by: syzbot+bfc9a0ccf0de47d04e8c@syzkaller.appspotmail.com
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>

Pull ceph fixes from Ilya Dryomov:
 "A patch to make sparse read handling work in msgr2 secure mode from
  Slava and a couple of fixes from Ziming and myself to avoid operating
  on potentially invalid memory, all marked for stable"

* tag 'ceph-for-6.18-rc8' of https://github.com/ceph/ceph-client:
  libceph: prevent potential out-of-bounds writes in handle_auth_session_key()
  libceph: replace BUG_ON with bounds check for map->max_osd
  ceph: fix crash in process_v2_sparse_read() for encrypted directories
  libceph: drop started parameter of __ceph_open_session()
  libceph: fix potential use-after-free in have_mon_and_osd_map()

With the previous commit revamping the timeout handling, started isn't
used anymore.  It could be taken into account by adjusting the initial
value of the timeout, but there is little point as both callers capture
the timestamp shortly before calling __ceph_open_session() -- the only
thing of note that happens in the interim is taking client->mount_mutex
and that isn't expected to take multiple seconds.

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>

When having a multiuser mount with domain= specified and using
cifscreds, cifs_set_cifscreds() will end up setting @ctx->domainname,
so it needs to be freed before leaving cifs_construct_tcon().

This fixes the following memory leak reported by kmemleak:

  mount.cifs //srv/share /mnt -o domain=ZELDA,multiuser,...
  su - testuser
  cifscreds add -d ZELDA -u testuser
  ...
  ls /mnt/1
  ...
  umount /mnt
  echo scan > /sys/kernel/debug/kmemleak
  cat /sys/kernel/debug/kmemleak
  unreferenced object 0xffff8881203c3f08 (size 8):
    comm "ls", pid 5060, jiffies 4307222943
    hex dump (first 8 bytes):
      5a 45 4c 44 41 00 cc cc                          ZELDA...
    backtrace (crc d109a8cf):
      __kmalloc_node_track_caller_noprof+0x572/0x710
      kstrdup+0x3a/0x70
      cifs_sb_tlink+0x1209/0x1770 [cifs]
      cifs_get_fattr+0xe1/0xf50 [cifs]
      cifs_get_inode_info+0xb5/0x240 [cifs]
      cifs_revalidate_dentry_attr+0x2d1/0x470 [cifs]
      cifs_getattr+0x28e/0x450 [cifs]
      vfs_getattr_nosec+0x126/0x180
      vfs_statx+0xf6/0x220
      do_statx+0xab/0x110
      __x64_sys_statx+0xd5/0x130
      do_syscall_64+0xbb/0x380
      entry_SYSCALL_64_after_hwframe+0x77/0x7f

Fixes: f2aee329a68f ("cifs: set domainName when a domain-key is used in multiuser")
Signed-off-by: Paulo Alcantara (Red Hat) <pc@manguebit.org>
Reviewed-by: David Howells <dhowells@redhat.com>
Cc: Jay Shin <jaeshin@redhat.com>
Cc: stable@vger.kernel.org
Cc: linux-cifs@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>

lookup_mnt_ns() already takes a reference on mnt_ns.
grab_requested_mnt_ns() doesn't need to take an extra reference.

Fixes: 78f0e33cd6c93 ("fs/namespace: correctly handle errors returned by grab_requested_mnt_ns")
Signed-off-by: Andrei Vagin <avagin@google.com>
Link: https://patch.msgid.link/20251122071953.3053755-1-avagin@google.com
Signed-off-by: Christian Brauner <brauner@kernel.org>

Pull xfs fix from Carlos Maiolino:
 "A single out-of-bounds fix, nothing special"

* tag 'xfs-fixes-6.18-rc7' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  xfs: fix out of bounds memory read error in symlink repair

Pull smb client fixes from Steve French:

 - Fix potential memory leak in mount

 - Add some missing read tracepoints

 - Fix locking issue with directory leases

* tag 'v6.18-rc6-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6:
  cifs: Add the smb3_read_* tracepoints to SMB1
  cifs: fix memory leak in smb3_fs_context_parse_param error path
  smb: client: introduce close_cached_dir_locked()